Discrimination of Junctions in Line Drawing by Computer

For discrimination of the common W-junction and Y-junction in the labels of line drawing for a three-dimensional manifold plane surface with trihedral vertices, the existing algorithms are almost using angles between two adjacent lines and W-junction and Y-junction's definitions, and other complex methods. This passage gives four methods with their detailed mathematical inference processes in order to use these algorithms implemented by computer. The algorithms listed are Angle Summation method and Points to the Line method, Triangle methods which are the Triangle Area method and the Cross method. When the computer programs discriminate junctions, by comparison, the Angle Summation method and Points to the Line method are less efficacious than the Triangle method, and Cross method is more efficacious than the Triangle Area method in the Triangle method.

Line drawing via saliency map and ETF

Line drawing is a means of superior visual communication which can effectively convey useful information to viewers.Artists usually draw what they see rather than what exists,which means the most attractive object is emphasized while the rest are inhibited.Moreover,artists draw the whole object with coherent lines instead of fractured lines,which also contribute to the outstanding visual effect.From these perspectives,generating line drawings with saliency and coherence remains a great challenge.Existing line drawing generation methods ignore these important properties and cannot generate coherent lines in some cases since they do not take into account how artists draw a picture.To this end,a novel saliency-aware line drawing method was proposed to better grasp the viewer’s attention on an image.First,a saliency enhanced line extraction method combining saliency map and edge tangent flow was proposed to ensure the saliency and coherence of lines,especially in salient but low contrast areas.Then,the salient information was highlighted while irrelevant details were eliminated by inhibiting lines in less salient areas to enhance the saliency of the line drawing.Finally,the transparency of lines was adjusted to further emphasize important information.Various results showed that our method can generate line drawings with better visual saliency and coherence than the state-of-the-art methods.

Surveys on line drawing simplification for Chinese cultural computing

In the recent decade,many approaches of rough line drawing simplification were proposed,but they are not well summarized yet,especially from the perspective of Chinese cultural computing.In this paper,a comprehensive review of existing line drawing simplification methods was presented,including their algorithms,advantages/disadvantages,inputs/outputs,datasets and source codes,etc.For raster line drawings,related simplification work was discussed according to four main categories:fitting-based methods,tracing-based methods,field-based methods,and learning-based methods.For vector line drawings,a deep investigation was introduced for two major steps of simplification:stroke grouping and stroke merging.Finally,conclusions were given,key challenges and future directions of line drawing simplification for Chinese traditional art were thoroughly discussed.

Stylized strokes for coherent line drawings

Temporal coherence is one of the central challenges for rendering a stylized line. It is especially difficult for stylized contours of coarse meshes or nonuniformly sampled models, because those contours are polygonal feature edges on the models with no continuous correspondences between frames. We describe a novel and simple technique for constructing a 2D brush path along a 3D contour. We also introduce a 3D parameter propagation and re-parameterization procedure to construct stroke paths along the 2D brush path to draw coherently stylized feature lines with a wide range of styles. Our method runs in real-time for coarse or non-uniformly sampled models, making it suitable for interactive applications needing temporal coherence.

Drawing a Line in the Sand

An Inner Mongolian woman takes on the desert and converts extensive arid regions into arable land by Ni Yanshuo CONVERTING vast tracks of desert into arable land is no easy task, even using the most advanced technology.Yet a woman who hails from north China’s Inner Mongolia Autonomous Region met this challenge head on.Using the helping hands of other determined women,she has made remarkable progress in pushing back the sands of time.

Exploring Local Regularities for 3D Object Recognition

In order to find better simplicity measurements for 3D object recognition, a new set of local regularities is developed and tested in a stepwise 3D reconstruction method, including localized minimizing standard deviation of angles(L-MSDA), localized minimizing standard deviation of segment magnitudes(L-MSDSM), localized minimum standard deviation of areas of child faces(L-MSDAF), localized minimum sum of segment magnitudes of common edges(L-MSSM), and localized minimum sum of areas of child face(L-MSAF). Based on their effectiveness measurements in terms of form and size distortions, it is found that when two local regularities: L-MSDA and L-MSDSM are combined together, they can produce better performance. In addition, the best weightings for them to work together are identified as 10% for L-MSDSM and 90% for L-MSDA. The test results show that the combined usage of L-MSDA and L-MSDSM with identified weightings has a potential to be applied in other optimization based 3D recognition methods to improve their efficacy and robustness.

Psychological potential field and human eye fixation on binary line-drawing images: A comparative experimental study

Quantitatively evaluating the psychological and perceptual effects of objects is an important issue,but is difficult. In cognitive studies, the psychological potential field(PPF), which represents psychological intensities in vision and can be calculated by applying computational algorithms to digital images, may help with this issue. Although studies have reported using the PPF to evaluate psychological effects, such as impressions, detailed investigations on how the PPF represents psychological perception and its limitations have not yet been performed. Another relevant tool is the fixation map, which visualizes human eye fixations;this map is generated from actual measurements acquired by eye-tracking and does not represent psychological effects directly. Although the PPF and the fixation map are based on visual imaging, they have never been compared. In this paper, we do so for the first time, using psychological and perceptual properties of line-drawing images. The results demonstrate the difference between these methods, including their representation of different properties with respect to visual perception. Moreover, the similarity between the two methods highlights the possibility of assessing perceptual phenomena such as categorization and cognition of objects based on human vision.

Portrait drawing from corresponding range and intensity images

We propose a real-time rendering system for automatically creating a caricature drawing, i.e., an exaggerated portrait, of a human face, based on simultaneous use of a range image (or 3D mesh) and a registered photograph of the same face. Combining these information sources provides complementary information. Significant geometric lines such as occluding contours and suggestive contours are extracted from the range data, while textured areas corresponding to shading features are extracted from the photograph. These are combined, and then distorted to produce the final caricature. The final output may be produced using a choice of non-photorealistic rendering styles. Our system method works well for low resolution range images; for these it is fast enough to allow the viewpoint to be chosen in real time. The final output combines significant lines, textured areas, and optional shading, giving a pleasing result which preserves not only the shape cues of the geometric description, but also other essential visual characteristics of the facial image that cannot be deduced from geometry alone.

Where Do We Draw the Line With Online Manhunts?

In early July, a manhunt message posted on dahe.cn, a local Web portal in central China’s Henan Province, caused great concern among netizens. In the post, Zhao Guanle, a police officer in Ruyang County who was investigating several ATM fraud cases, provided a screenshot of the face of a young man who was suspected of committing the fraud and asked netizens knowing the man to help the police

Where Do You Draw the Line In Copyright Infringement?

Famous Chinese film director Chen Kaige has made a big comeback with the release of his visually breathtaking movie The Promise, a $44 million mythological epic said to be the most expensive film in the history of Chinese cinema. As with every project Chen is involved in, the film has drawn extensive attention before and after its screening. Having been given a Golden Globe nomination for